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Adjusting Steering Head

19916 Views 22 Replies 10 Participants Last post by  Grae_ST
I'm going to adjust my steering head sometime in the next couple days and grease the bearing. The service manual says to torque the adjuster to 32nm as part of the process. In reading up on this on several threads nobody seems to be doing the torque business and just using anything from some kind of bicycle wrench to vice grips. Do you need to get some kind of special deep or thin walled socket to do this job and does anyone know the right size? I think it may be 36mm but ??????
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From many, many posts on another website most of the steering head bearing failures were at the hands of the Triumph Factory, or a trained mechanic doing a scheduled service, so I wouldn't adjust it tho the factory specification.

The problem is the top bearing is used in an improper loading situation. A standard ball bearing is NOT designed for much side loading at all. When you adjust the races the top bearing is being side loaded in the Triumph setup. It is a standard radial ball bearing and not designed for this type of load. The lower bearing is a tapered roller bearing and is the one that does (and should) take the majority of the loads in their setup. The top bearing should only keep things centered and not be placed under much load (torque setting) at all.

Here's how I do them and I still have the original bearings in mine after 25k. Some people have gone through three or more sets during that time and were replaced by the dealer under warranty claims.

1. Get the front wheel off the ground. (An inch or two is fine) This way you can get some room to grease the lower tapered bearing which is not a sealed bearing. (it will be pretty dry!)

2. Remove the top triple tree. (Do not re-tighten the pinch bolts until all the adjustments have been finished). This will allow the wheel assembly to drop and give you access to grease the lower bearing.

3. Take out the top bearing (it's sealed) and make sure it doesn't have any rough spots. If it does replace it. They're only about $3.00! (unless you go to the dealer!) Part #6205-2RS

4. When you put it all back together only tighten the adjusting nut as much as you can WITH THE SOCKET HELD IN YOUR HAND! Do not use any tools here, just the bare socket and hand tighten it!

5. Rotate the handle bars back and forth to distribute the grease you applied to the lower bearing.

6. Loosen the adjusting nut and repeat step #4.

7. Be sure the assembly does not tighten (adjusting nut turns) when you tighten the top nut. Your done! And you're top bearing will not die because it was side loaded excessively. Don't forget to tighten the pinch bolts on the top triple tree now.

Now, there are a couple of fixes for this as well. They both require the replacement of the top bearing which is being used incorrectly unless it is not put under any side load, which is virtually impossible.

Replace the top bearing with an ANNULAR CONTACT bearing which is designed for radial as well as side loading. They can be had for about $12.00 and are a complete drop in replacement. Part #7205 Annular contact bearings.

Or replace the top bearing with another tapered roller bearing. These are also a drop in replacement except they are just under 1/16" to wide which really shouldn't bother anything. The top triple tree needs to be removed anyway and readjusted for bearing replacement or if you're just doing a bearing check. Part #30205 Tapered roller bearing. About $10.00 each.

The tapered roller bearing will take more side loading, but the Annular will be more than enough here. Either one will be fine.

Stock Replacement Bearing
Annular Contact Bearing
Tapered Roller Bearing

A little tip I used in using these bearings in not so clean environments such as this sense both the Annular and Tapered bearings are not sealed. Find an 'O' ring that will just lay around the inner race and cover the area where the rollers and grease would get dirt in them. Get the 'O' ring thick enough to just be compressed slightly when assembled in the assembly. This will keep out 95% of the dirt and keep the grease in the bearing as well.

[ This message was edited by: Stlakid on 2006-10-10 03:21 ]
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Thanks for the response Stlakid, it will be useful as I need to adjust and/or replace mine sometime soon
Outstanding description. Thanks.
Excellent info Skatlid. Thanks,

That's what I really enjoy about this site. The sharing of info - freely with the experience to back it up.

Great job :gpst:
Just drug out the service manual and found an interesting section. The above adjusting technique was my own which I know to work and not damage the top bearing. This is the Triumph adjustment technique word for word.....


1. Raise and support the front of the motorcycle.

2. Slacken the pinch bolts ON THE TOP YOKE ONLY.

3. Slacken the headstock top nut.

4. Slacken the handlebar clamp screws.

5. Adjust the bearing free-play as folows....

A. Tighten the adjuster nut to 32Nm.
B. Loosen the nut and then re-tighten by hand until any bearing
free play is eliminated.


Correct adjustment is attained when the bearing play is eliminated without preloading the bearings.

It also recommends using Anti-Seize compound on the threads.
It seems that people (including the service department) would stop reading at the point of "Tighten the adjusting nut to 32Nm" It would seem that the torque setting is used to 'Set' the bearings only before actual adjustment by hand.
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I read that section prior to initiating this thread and I read it exactly as you explain, but the way it is printed it is very confusing. I actually read it several times and compared it to a bunch of threads on several lists. The additional info did kinda sorta clarify it but the STlakid post is the only thing that flat nails it. Again, great post.
Nice job Stlakid. Thanks,

Hey STLAkid,
I have tried to remove the top of the tripple tree and it isn't cooperating. The forks are completely out. The top nut is off but it isn't coming out so I can get at the adjuster nut. Am I missing something????
Finally got it off. Took progressively thicker flat tip screwdrivers and wedged them between the top plate and the adjusting nut. Apply hammer to screwdriver and watch it creep up and off. The plate had frozen to the axle of the triple tree between the top (smaller) and the wider bottom threads. So far this makes the front axle bolt, rear axle stake nut, and two or three sprocket bolts that have been frozen due to corrosion or galvanic action. I'm beginning to think Triumphs are bio-degradeable.

The adjusting nut definitely isn't a 36mm, maybe a 38. In any event. This is the last time I grease these frickin' bearings. It ain't like they are hitting 10K rpm.

Tapered roller

1.25 millimeters = 0.0492125984 inches

1/16" = 0.0625

1/20" = .05

Any way did I mention that despite being american that the SAE system sucks as compared to metric units....

I'm guessing that the 1.25mm increase in width does'nt matter...

Another lowbuck smart mod to add to the list..
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There is a tapered roller bearing at the bottom of the triple tree that really does all the work. the one at the top pretty much just keeps the axle (or whatever you want to call it) centered. So using a tapered roller bearing is IMO overkill. I just replaced the top bearing with the anular contact bearing but right now I'm not all that sure if greasing the bottom bearing is worth it. It might be best to run it till it breaks.
Glad you got it figured out Rodney. The assembly is under a little load when you loosen things up because the weight of the tire is trying to drop straight down, but the steering head is at an angle.

I never took out my bottom bearing to grease it. Just let the assembly drop about an inch out of the crown and get some fresh grease on the lower bearing. I had my front wheel off the ground about 1.5" so I just let it drop until it hit the ground. Try to get things in alignment when you reassemble the bearings as the forks will try to pull them out of alignment without both triple trees in place and you will remove aluminum from the top tree when you try to reassemble it if it's not aligned. As me how I know!
Because I was replacing the top bearing I had to take it out. You have to put something up the neck to knock out the old bearing because it is press fitted. You are correct about lining things up but I didn't see any aluminum. I'm still not done because the frozen top plate made a 15 minute job take a couple of hours.
I guess that's another one of the joys of living in California, it doesn't get that wet here. My top bearing slipped right out with my fingers once the shaft had been lowered out of it. Sounds like you have a handle on things though.
It's back together. If you want to see pics of this stuff look in
where you'll see stuff like

After action report says the nut is 38mm or 1.5 inches. Old bearing has to be knocked out and new driven in place. 32nm is way too much and will lock up steering.
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The 32 Nm is simply to set the bearings in place, they then need to be backed off to zero preload/zero play. I guess a little preload is better than a little play. Any play will allow the bearings to hammer against the race and dimple them up pretty quick.
I'm not sure what I wound up with but it wasn't anywhere near the 32nm. When I put that torque on, my bars wouldn't even turn. Actually, when the top piece initially came off, you could spin the adjusting nut with two fingers. Funny, it wasn't nicked, notched or whatever, the bars seemed to be totally free and there was no play but I'll swear it stears better now.
Thought I'd dig up this post, as I'm having probs with my head bearings.

As the 20000Km service is fast approaching, i figure it's a good time to fit Tapered Roller Bearings Bottom and Top.

So, my question is are these the correct dimensions for my '07 Sprint or have they changed?

Tapered roller

The fiche on BikeBandit shows different dimensions:- 30 x 55 x 17.

Thanks in advance for your help!!

Cheers, G :D
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